/*
 * Alloy Analyzer
 * Copyright (c) 2002 Massachusetts Institute of Technology
 *
 * The Alloy Analyzer is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * The Alloy Analyzer is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with the Alloy Analyzer; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

package alloy.bool;

/**
 * Boolean expression meaning "set the value of the given {@link BoolSwitch} to the given
 * value, and evaluate the given {@link BooleanFormula}.  For more explanation of Boolean
 * switches, see the {@link alloy.bool} package documentation.
 */
class SetVarExpr extends GBF_OneExprBase  {
    /**
     * {@link BoolSwitch} whose {@linkplain BoolSwitch#_switchValue value} should be 
     * {@linkplain BoolSwitch#setVarValue set} to the value of {@link #var} when
     * a {@linkplain GBF_V visitor} visits this switch setter node.
     */
    final BoolSwitch var;
    
    /**
     * The value to which the switch {@link #var} should be set when a {@link GBF_V visitor}
     * visits this switch setter node.
     */
    final long val;

    /**
     * Construct a switch setter node thats sets a given switch to the given value.
     */
    SetVarExpr(BoolSwitch var_, long val_, BooleanFormula formula_) {
	super(formula_); this.var = var_; this.val = val_;
    }

    protected Object handleVisitor(GBF_V visitor_) { return visitor_.forSetVarExpr(this); }
    public String toString() { return "[SetVar: " + var + "=" + val + ", " + expr + "]"; }
}
